Jordan JXR6 linear array with JX92s

[xcortes]

I need to build a set of HT speakers with the following requirements:

At least 93 dB efficient
Very low profile and footprint
Wall mounted

I'm thinking of building the three fronts asfollows: a vertical linear array consisting of four JXR6 Jordan drivers and a "bass unit" consisting of one JX92s unit. I would biamp using 300B SET amps (8W) for the top and gainclones (32W) for the JX92s. I would probably add a 6dB PLLXO at the gainclones.

Maybe 4 liters for the four JXR6s and vented 7 liter for the JX92s to get me to the 50's and from there all channels to a powered subwoofer.

For the surrounds I could use only one JXR6 per channel because I would assume 98dB there is enough.

I don´t know if I would position the JX92s below or on the side of the linear arrays. On the side would be better to make the center channel shorter.

Does this design show any promise?

thanks

xavier

 

[ScottG]

I need to build a set of HT speakers with the following requirements:

At least 93 dB efficient
Very low profile and footprint
Wall mounted

I'm thinking of building the three fronts asfollows: a vertical linear array consisting of four JXR6 Jordan drivers and a "bass unit" consisting of one JX92s unit. I would biamp using 300B SET amps (8W) for the top and gainclones (32W) for the JX92s. I would probably add a 6dB PLLXO at the gainclones.

Maybe 4 liters for the four JXR6s and vented 7 liter for the JX92s to get me to the 50's and from there all channels to a powered subwoofer.

For the surrounds I could use only one JXR6 per channel because I would assume 98dB there is enough.

I don´t know if I would position the JX92s below or on the side of the linear arrays. On the side would be better to make the center channel shorter.

Does this design show any promise?

thanks

xavier

..everything sounded good (except for price).. until I actually re-read what the design was for.

In my experience HT calls for a "punchy" visceral sound.. I really don't think that the Jordan's will accomidate this need.

It MAY also have a problem with higher freq. effects and off-axis dispersion from the drivers.

This is what I'd recomend:

http://www.radianaudio.com/products/ceiling/8_ceiling.php?viewT=ceiling&viewC=8_ceiling

driver (and I think stock crossover) reviewed here:

http://www.enjoythemusic.com/magazine/equipment/0702/galanteaudio.htm

 

[navin]

I need to build a set of HT speakers with the following requirements:

At least 93 dB efficient
Very low profile and footprint
Wall mounted

1. why a 300B for HT? You could chip amp all 4-7 channels.
2. a linear array of 4 JX6 should be enough for front left and right another alternate might be Jim Griffins JX92+G2Si combo
3. for the rears I would suggest atleast 2 JX6 or 1 JX92 in a 3-4 liter box.
4. The Jordans are not 93db efficient. If you want that a bigger box with a FE167 (see Bob Brines) might be required. Bob Brines has a "bookshelf" version usng the 167 that might be wall mounted atbeit it would be a larger box.
5. For HT you might need a bit more punch. If you are not using a center channel (phantom center) John K's ZD5 or even a linear array of smaller drivers (http://www.zaphaudio.com/smalltest/) might work.

 

[Spasticteapot]

While I'm no good at describing how "punchiness" can be achieved, I can say that less efficient speakers may be better here.

A less expensive bet might be to use a set of high-treble fullrange drivers (Hi-Vi B3S' measurements are good through 20khz with minimal dropoff) with a well-made woofer. (The Silver Flute drivers are economical at about $30 each, and are pretty flat down to 40hz!)

As a side note, the B3S, like many small high-treble FR speakers is a horrendously inefficient speaker - under 80db efficient with the Zaphaudio notch filter. The best solution is to use four in a series/parallel configuration, which should, coincidentally, give about 93db/w if I did'nt flub my math too badly. Alternately, a more efficient speaker like the FE83 could be used, but the price of the TangBand and Hi-Vi drivers is much, much lower.

I would also reccomend going with some chip-amps and a simple active crossover . A LM4780 and a quad op-amp per side would be ideal; two op-amps would be used per channel for the -12db/octave 1st order crossover, and half of the LM4780 (with adjusted gain for the woofer and FR sections) would be used for the top and bottom, respectively.


I'm hoping to build a pair of these myself - the cost is only about 100$ for raw drivers, and the active crossover should'nt be more than 20$ or so. The B3Ss are supposed to work very well in an open baffle, too - I'm hoping to use a sheet of polycarbonate.

 

[navin]

So there are a number of options

1. a fullrange with a helper tweeter a la Jim Griffns JX92 G2si
2. if sensitivity is vital Bob Brines FE167 (92-93 db sens)
3. A line array of 4-8 3" drivers like the HiVi B3S, Aura NS193 or Tangband W3871, Fostex FE83/87 FF85K etc...(another configuration could be an active bessel array of these drivers using chip amps)
4. Or a "traditional" 2 way like the John K's (zaphaudio) ZD5.